The station was closed for more than two hours. It re-opened around 2:30 p.m. but the MBTA said riders should expect residual delays.

Pesaturo told WBZ-TV’s Jon Keller one trolley was making a stop on the outbound platform and it rear-ended a train that had been parked on the same track. Pesaturo described the crash as “low impact” and there was no derailment.

WBZ-TV’s Jim Armstrong reports

But some witnesses told Keller the impact was more than a bump and they were tossed to the floor when it happened.

A man who was a passenger on one of the trains told WBZ it felt like a bomb had gone off and that “everybody just went violently into one direction.”

A view from inside the station in the moments after the crash. (Photo courtesy: Chris Chanyasulkit/Twitter)

The fire department said no one was trapped, but several people were taken out of the underground station on stretchers.

Chris Chanyasulkit got on the Green Line at Park Street and had barely had a chance to sit down when the accident happened.

“All of a sudden you just felt this bang,” she explains. “Everybody lurched forward, I lurched forward, and there was this loud screaming,”

“It just happened within one stop, and I was thinking, ‘I should’ve walked!’”

The Brookline resident spent a couple of hours at the emergency room, where she learned she has whiplash, along with other assorted bumps and bruises.

“I’m very thankful; it could have been a lot worse,” she says. “But at the same time, it’s kind of scary.”